Subject to Completion, dated [    •    ], 2012

The information in this prospectus is not complete and may be changed. We may not sell these securities until the registration statement filed with the Securities and Exchange Commission is effective. This prospectus is not an offer to sell these securities and it is not soliciting an offer to buy these securities in any state or jurisdiction where the offer or sale is not permitted.

Prospectus

[    •    ] American depositary shares

Representing [    •    ] common shares

This is the initial public offering of American depositary shares, or ADSs of Cementos Pacasmayo S.A.A. We are selling [    •    ] ADSs. Each ADS represents [    •    ] common shares. We expect the initial public offering price will be between US$[    •    ] and US$[    •    ] per ADS.

We have applied for listing of our ADSs on the New York Stock Exchange under the symbol "CPAC". Our common shares and our non-voting investment shares are listed on the Lima Stock Exchange ( Bolsa de Valores de Lima ) under the symbols "CPACASC1" and "CPACASCI1", respectively.

On [    •    ], 2012, the last reported sales price of our common shares on the Lima Stock Exchange was S/.[    •    ] per common share (equivalent to US$[    •    ] per ADS based on the exchange rate on such date).

We have granted the underwriters an option for a period of 30 days to purchase from us up to additional ADSs, representing [    •    ] common shares, to cover over-allotments, if any.

Investing in the ADSs involves a high degree of risk. See "Risk factors" beginning on page 16.

Neither the U.S. Securities and Exchange Commission nor any state securities commission has approved or disapproved these securities or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

Neither the ADSs nor the offering has been or will be registered in the Republic of Peru and therefore are not and will not be subject to Peruvian laws applicable to public offerings in Peru. The information contained in this prospectus has not been approved or disapproved by the Peruvian Securities Commission ( Superintendencia del Mercado de Valores) . The ADSs may not be offered or sold in Peru except in compliance with the securities laws of Peru.

Sole Bookrunner

J.P. Morgan

Joint Lead Manager

Santander

                           , 2012

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We are responsible for the information contained in this prospectus. We have not authorized anyone to give you any other information and we take no responsibility for any other information that others may give you. The information contained in this prospectus is accurate only as of the date of this prospectus, regardless of the time of delivery of this prospectus or of any sale of ADSs.

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Through and including                           , 2012 (the 25th day after the date of this prospectus), federal securities law requires all dealers that effect transactions in our ADSs, whether or not participating in this offering, to deliver a prospectus. This requirement is in addition to the dealers' obligation to deliver a prospectus when acting as underwriters and with respect to their unsold allotments or subscription.

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This prospectus has been prepared on the basis that all offers of ADSs in any Member State of the European Economic Area which has implemented the Prospectus Directive (each, a "Relevant Member State") will be made pursuant to an exemption under the Prospectus Directive from the requirement to produce a prospectus for offers of the ADSs. Accordingly, any person making or intending to make any offer of ADSs within the European Economic Area that are the subject of the offering contemplated in this prospectus should only do so in circumstances in which no obligation arises for us or the underwriters to produce a prospectus for such offer. Neither we nor the underwriters have authorized, or hereby authorize, the making of any offer of ADSs in circumstances in which an obligation arises for us or the underwriters to publish a prospectus for such offer. "Prospectus Directive" means Directive 2003/71/EC (and amendments thereto, including the 2010 PD Amending Directive, to the extent implemented in the Relevant Member State), and includes any relevant implementing measure in the Relevant Member State and the expression 2-1-PD Amending Directive means Directive 2010/73/EU.

The distribution of this prospectus and the offering and sale of the ADSs in certain jurisdictions may be restricted by law. Persons who receive this prospectus must inform themselves about and observe any such restrictions. This prospectus does not constitute an offer of, or an invitation to purchase, any of the ADSs in any jurisdiction in which such offer or invitation would be unlawful.

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Presentation of financial and other information

Certain definitions

All references to "we," "us," "our," "our company" and "Cementos Pacasmayo" in this prospectus are to Cementos Pacasmayo S.A.A., a publicly-held corporation ( sociedad anónima abierta ) organized under the laws of Peru, and, unless the context requires otherwise, its consolidated subsidiaries. The term "U.S. dollar" and the symbol "US$" refer to the legal currency of the United States; and the term "nuevo sol" and the symbol "S/." refer to the legal currency of Peru.

Financial information

Our consolidated financial statements included in this prospectus have been prepared in nuevos soles and in accordance with International Financial Reporting Standards ("IFRS") as issued by the International Accounting Standards Board ("IASB").

Historically, our financial statements have been prepared in accordance with generally accepted accounting principles in Peru ("Peruvian GAAP") and audited in accordance with generally accepted auditing standards in Peru. In accordance with Peruvian law, we will be required to present our financial statements under IFRS beginning with our financial statements for the year ended December 31, 2011. Peruvian GAAP differs in material respects from IFRS. For this reason, our financial information presented in accordance with Peruvian GAAP, which we publish in Peru, is not directly comparable to our financial information prepared in accordance with IFRS included in this prospectus. For a description of the principal adjustments made to our Peruvian GAAP consolidated financial statements to transition to IFRS, see note 2 to our annual audited consolidated financial statements in this prospectus.

In this prospectus, we present Adjusted EBITDA, a non-GAAP financial measure. A non-GAAP financial measure is generally defined as one that purports to measure financial performance, financial position or cash flows but excludes or includes amounts that would not be so adjusted in the most comparable IFRS measure. We present Adjusted EBITDA because we believe it provides investors with a supplemental measure of the financial performance of our core operations that facilitates period-to-period comparisons on a consistent basis. Our management also uses Adjusted EBITDA from time to time, among other measures, for internal planning and performance measurement purposes. Adjusted EBITDA should not be construed as an alternative to profit or operating profit, as an indicator of operating performance, as an alternative to cash flow provided by operating activities or as a measure of liquidity (in each case, as determined in accordance with IFRS). Adjusted EBITDA, as calculated by us, may not be comparable to similarly titled measures reported by other companies, including those in the cement industry. For a calculation of Adjusted EBITDA and a reconciliation of Adjusted EBITDA to the most directly comparable IFRS financial measure, see "Selected financial and operating data."

We have translated some of the nuevos soles amounts contained in this prospectus into U.S. dollars for convenience purposes only. Unless the context otherwise requires, the rate used to translate nuevos soles amounts to U.S. dollars was S/.2.773 to US$1.00, which was the exchange rate reported on September 30, 2011 by the Peruvian Superintendency of Banks, Insurance and Private Pension Fund Administrators ( Superintendencia de Banca , Seguros y AFPs, or " SBS ") . The Federal Reserve Bank of New York does not report a noon buying rate for nuevos soles. The

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U.S. dollar equivalent information presented in this prospectus is provided solely for convenience of investors and should not be construed as implying that the nuevos soles amounts represent, or could have been or could be converted into, U.S. dollars at such rates or at any other rate. See "Exchange rates" for information regarding historical exchange rates of nuevos soles to U.S. dollars.

Certain figures included in this prospectus have been subject to rounding adjustments. Accordingly, figures shown as totals in certain tables may not be arithmetic aggregations of the figures that precede them.

Market information

We make estimates in this prospectus regarding our competitive position and market share, as well as the market size and expected growth of the construction sector and cement industry in Peru. We have made these estimates on the basis of our management's knowledge and statistics and other information from the following sources: the Central Bank of Peru ( Banco Central de Reserva del Perú ); the National Statistical Institute of Peru ( Instituto Nacional de Estadística e Informática, or "INEI"); the Association of Cement Producers in Peru ( Asociación de Productores de Cemento, or "ASOCEM"); Fondo Mi Vivienda S.A. ("Fondo Mi Vivienda"), a housing fund owned and administered by the government of Peru; ADUANET, a website administered by the Peruvian Tax Superintendency ( Superintendencia Nacional de Administración Tributaria, or "SUNAT"); the Peruvian Chamber of Construction ( Cámara Peruana de la Construcción ); The International Cement Review, a website that provides cement manufacturing information; the World Business Council for Sustainable Development, an association of approximately 200 companies worldwide focused on sustainability and development matters; and the U.S. Geological Survey, a U.S. government science organization. We believe these estimates to be accurate as of the date of this prospectus.

Offering information

All amounts contained in this prospectus that have been adjusted to reflect the estimated net proceeds of the global offering are based upon the sale of ADSs at an assumed public offering price of US$[    •    ] per ADS (the mid-point of the price range set forth on the cover page of this prospectus). Unless otherwise indicated, all information contained in this prospectus assumes no exercise of the underwriters' option to purchase up to [    •    ] additional ADSs, representing [    •    ] common shares, to cover over-allotments, if any. Unless otherwise indicated, information contained in this prospectus also assumes no purchase of up to [    •    ] non-voting investment shares (based on the issuance of [    •    ] common shares in this offering, including full exercise of the underwriters' over-allotment option) to be offered in the preemptive rights offer that we are required to undertake pursuant to Peruvian law following this offering.

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Forward-looking statements

This prospectus contains forward-looking statements. Forward-looking statements convey our current expectations or forecasts of future events. These statements involve known and unknown risks, uncertainties and other factors, including those listed under "Risk factors," which may cause our actual results, performance or achievements to differ materially from the forward-looking statements that we make.

Forward-looking statements typically are identified by words or phrases such as "may," "will," "expect," "anticipate," "aim," "estimate," "intend," "project," "plan," "believe," "potential," "continue," "is/are likely to," or other similar expressions. Any or all of our forward-looking statements in this prospectus may turn out to be inaccurate. Our actual results could differ materially from those contained in forward-looking statements due to a number of factors, including:

•

general economic, political and social risks inherent to conducting business in Peru;

•

exchange rates, inflation and interest rates;

•

the entry of new competitors into the market we serve;

•

construction activity levels, particularly in the northern region of Peru;

•

private investment and public spending in construction projects;

•

unpredictable natural disasters, such as floods and earthquakes affecting the northern region of Peru;

•

availability and prices of energy, admixtures and raw materials;

•

changes in the regulatory framework, including tax, environmental and other laws;

•

the successful expansion of our production capacity;

•

our ability to compete with potential substitutes of cement products that may be introduced in the Peruvian construction industry;

•

our ability to maintain and expand our distribution network;

•

our ability to retain and attract skilled employees;

•

our ability to develop successfully the phosphate rock and brine deposits in our fields;

•

our ability to obtain financing for our phosphate and brine projects; and

•

other factors discussed under "Risk factors."

The forward-looking statements in this prospectus represent our expectations and forecasts as of the date of this prospectus. Except as required by law, we undertake no obligation to update or revise publicly any forward-looking statements, whether as a result of new information, future events or otherwise, after the date of this prospectus.

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Risk factors

An investment in our ADSs involves a high degree of risk. In addition to the other information in this prospectus, you should carefully consider the risks described below before purchasing our ADSs. If any of the following risks actually occurs, our business, results of operations or financial condition will likely suffer. As a result, the trading price of our ADSs may decline, and you may lose part or all of your investment.

Risks relating to Peru

Economic, social and political developments in Peru could adversely affect our business, financial condition and results of operations.

All of our operations are conducted in Peru and depend on economic and political developments in the country. As a result, our business may be materially and adversely affected by economic downturns, currency depreciation, inflation, interest rate fluctuation, government policies, regulation, taxation, social instability, political unrest, terrorism and other developments in or affecting the country, over which we have no control.

The cement industry in Peru is highly dependent on construction activity in the country, which, in turn, depends on the purchasing power of consumers and, to a lesser extent, commercial and infrastructure investment. Adverse economic conditions could adversely affect construction activity and result in a decrease in demand for cement products.

In the past, Peru has experienced periods of severe economic recession, large currency devaluation and high inflation. In addition, Peru has experienced periods of political instability, which have led to adverse economic consequences. We cannot assure you that Peru will not experience similar adverse developments in the future.

While Peru has experienced economic growth in the recent past, political tensions, high levels of poverty and unemployment, and social conflicts with local communities continue to be pervasive problems in Peru. In recent months, certain areas in the south and the northern highlands of Peru with significant mining developments have experienced strikes and protests related mainly to the environmental impact of metallic mining activities, which have resulted in political tensions, commercial disruptions and a climate of uncertainty with respect to future mining projects. Future government policies in response to social unrest could include, among other things, increased taxation, as well as expropriation of assets. These policies could materially and adversely affect the Peruvian economy and, as a result, our business, financial condition and results of operations.

The newly elected Peruvian president may not maintain recent economic policies, which could adversely affect our business, financial condition and results of operations.

On July 28, 2011, Ollanta Humala became president of Peru. The election of President Humala initially generated political and economic uncertainty. President Humala's presidential campaign was based on a platform of poverty reduction and wealth redistribution, including by means of interventionist policies, although since his inauguration President Humala has taken steps indicating that his administration will focus on more centrist economic policies. For instance, the new administration recently ratified Julio Velarde as president of the Central Bank of Peru and appointed Luis Miguel Castilla as minister of economy and finance, both of whom served

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as senior members of the previous administration and have been strong proponents of open market policies. We cannot assure you that the new administration will not pursue significant changes in the country's economic policies and regulations, including tax increases, higher minimum wages and employee pension requirements, stricter environmental standards, greater rights for local indigenous communities and more proactive or interventionist government policies in certain sectors of the economy that have been underserved by the private sector. Such policies, if implemented, could materially and adversely affect the Peruvian economy and, as a result, our business, financial condition and results of operations.

In addition, President Humala's political party did not obtain a majority of the congressional seats which may potentially lead to a gridlock in the Peruvian Congress and create further political uncertainty.

Fluctuations in the value of the nuevo sol relative to the U.S. dollar could adversely affect our business, financial condition and results of operations.

Fluctuations in the value of the nuevo sol relative to the U.S. dollar could adversely affect Peru's economy. In addition, a depreciation of the nuevo sol could increase, in terms of nuevos soles, certain of our production costs. Substantially all of our revenues are denominated in nuevos soles. However, certain of our expenses, such as the purchase of coal and electricity, are denominated in U.S. dollars. In 2010, approximately 30.0% of our cost of sales were denominated in U.S. dollars. We currently do not hedge our foreign currency risk exposure. In the past the exchange rate between the nuevo sol and the U.S. dollar has fluctuated significantly. We cannot assure you that the value of nuevo sol against other currencies will not fluctuate significantly in the future, which could adversely affect the Peruvian economy and our business, financial condition and results of operations.

In addition, although Peruvian law currently imposes no restrictions on the ability to convert nuevos soles to foreign currency and transfer foreign currency outside of the country, in the 1980s and early 1990s Peru imposed exchange controls, including controls affecting the remittance of dividends to foreign investors. We cannot assure you that exchange controls in Peru will not be implemented in the future. The imposition of exchange controls could have an adverse effect on the economy and on your ability to receive dividends from us as a holder of ADSs.

Inflation could adversely affect our business, financial condition and results of operations.

Peru, like some other countries in Latin America, experienced periods of hyper inflation in the 1980s and high inflation in the early 1990s. In recent years, inflation has been relatively low, with an average annual inflation rate between 2006-2010 of 2.8%, as measured by the Peruvian Consumer Price Index ( Índice de Precios al Consumidor del Perú ) that is calculated and published by the INEI. If Peru experiences significant rates of inflation in the future, the economy could be adversely affected. In addition, high rates of inflation could increase our operating costs and adversely impact our operating margins if we are not able to pass the increased costs to consumers.

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Changes in tax laws may increase our tax burden and, as a result, could adversely affect our business, financial condition and results of operations.

The Peruvian government from time to time implements changes to tax regulations. Any such changes may result in increases to our overall tax burden, which would negatively affect our profitability. On September 29, 2011, the Peruvian government amended the Mining Royalty Law ( Ley de la Regalía Minera ) to increase taxation on metallic and non-metallic mining activities in Peru, which will adversely affect our results of operations beginning October 1, 2011. According to this amendment, companies engaged in mining activities in Peru will be required to pay mining royalty taxes on a quarterly basis in an amount equal to the greater of (i) an amount determined in accordance with a statutory scale of tax rates based on a company's operating profit margin that is applied to its operating profit, as adjusted by certain non-deductible expenses, and (ii) 1% of a company's net sales, in each case during the applicable quarter. Our future mining royalty tax payments will depend on our operating profit, operating profit margin and net sales. Based on our results of operations for 2010 and the nine months ended September 30, 2011, we estimate that our incremental mining royalty taxes, net of the applicable income tax effect, would have been approximately S/.4.6 million (US$1.7 million) and S/.3.5 million (US$1.3 million), respectively, if this amendment had been in effect during such periods. We cannot assure you that the Peruvian government will not implement additional changes to tax regulations in the future, which could adversely affect our business, financial condition and results of operations.

Earthquakes, flooding and other natural disasters could affect our business, financial condition and results of operations.

Peru is located in an area that experiences seismic activity and occasionally is affected by earthquakes. In 2007, an earthquake with a magnitude of 7.9 on the Richter scale struck the central coast of Peru, severely damaging the Ica region, located south of Lima. In addition, Peru, including the northern region where we operate and distribute our products, experiences from time to time severe rainfall and flooding, largely as a result of the climate pattern known as El Niño, which typically occurs every two to seven years. Although we have insurance covering damages caused by natural disasters, the occurrence of a severe natural disaster in the north of Peru could affect our facilities and temporarily disrupt our operations or the distribution of our products.

A resurgence of terrorism in Peru could adversely affect the Peruvian economy and, as a result, our business and results of operations.

In the past, Peru experienced significant levels of terrorist activity that reached its peak of violence against the government and private sector in the late 1980s and early 1990s. In the mid-1990s, terrorist groups suffered significant defeats, including the arrest of leaders, resulting in considerable limitations in their activities. Although terrorism no longer poses a significant threat in Peru, a small group of terrorists primarily related to drug traffickers continues to operate in remote mountainous and jungle areas in the central and southern regions of the country. A resurgence of terrorism could materially and adversely affect the Peruvian economy and, as a result, our business, financial condition and results of operations.

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The Peruvian economy could be affected by adverse economic developments in regional or global markets.

Financial and securities markets in Peru are influenced, to varying degrees, by economic and market conditions in regional or global markets. Although economic conditions vary from country to country, investors' perceptions of the events occurring in one country may adversely affect capital flows into and securities from issuers in other countries, including Peru.

The Peruvian economy was adversely affected by the political and economic events that occurred in several emerging economies in the 1990s, including in Mexico in 1994 and the Asian crisis in 1997, which affected the market value of securities issued by companies from markets throughout Latin America. Similar adverse consequences resulted from the economic crisis in Russia in 1998, the Brazilian currency devaluation in 1999 and the Argentine crisis in 2001. In addition, Peru's economy continues to be affected by events in the economies of its major regional partners and in developed economies that are trading partners or that affect the global economy. During the recent global economic and financial crisis, global conditions led to a slowdown in economic growth in Peru, slowing GDP growth in 2009 to 0.9%. In particular, the Peruvian economy suffered the effects of lower commodity prices in the international markets, a decrease in export volumes, a decrease in foreign direct investment inflows and, as a result, a decline in foreign reserves.

Adverse developments in regional or global markets in the future could adversely affect the Peruvian economy and, as a result, adversely affect our business, financial condition and results of operations.

Risks relating to our business and industry

We are subject to the possible entry of domestic or international competitors into our market, which could decrease our market share and profitability.

The cement market in Peru is competitive and is currently served by three principal groups which together supply substantially all of the cement consumed in the country. In the cement industry, the location of a production plant tends to limit the market that a plant can serve because transportation costs are high, reducing profit margins. Historically, we have supplied the northern region of Peru while the two other groups have supplied the central (which includes the Lima metropolitan area) and southern regions of Peru, driven principally by the location of production facilities and distribution focus. However, competition could intensify if other manufacturers decide to enter our market.

We may face increased competition if the other Peruvian cement manufacturers, despite incremental freight costs, expand their distribution of cement to the northern region of Peru, or if they develop a cement plant in the north, particularly if the cement markets in Lima or other areas of Peru become saturated. Some large foreign cement manufacturers have announced plans to build cement plants in the central region of the country. If competition intensifies in the central region of Peru due to the presence of foreign cement manufacturers or otherwise, it may have price repercussions in our market.

We also face the possibility of competition from the entry into our market of imported clinker, cement or other materials or products from foreign manufacturers, which may have

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significantly greater financial resources than us, particularly as production capacity continues to exceed depressed demand in other parts of the world and transportation costs decrease.

We may not be able to maintain our market share if we cannot match our competitors' prices or keep pace with the development of new products. If any of these events were to occur, our business, financial condition and results of operations could be adversely affected.

Demand for our cement products is highly related to housing construction in the northern region of Peru, which, in turn, is affected by economic conditions in the region.

Cement consumption is highly related to construction levels. Demand for our cement products depends, in large part, on residential construction in the north of Peru, which consists mostly of low-income families gradually building or improving their own homes. We estimate that in 2010 auto-construcción accounted for approximately 59% of our cement sales. Residential construction, in turn, is highly correlated to prevailing economic conditions in Peru. A decline in economic conditions would reduce household disposable income and cause a significant reduction in residential construction, leading to a decrease in demand for cement. As a result, a deterioration in economic conditions in the northern region of Peru would have a material adverse effect on our financial performance. We cannot assure you that growth in Peru's GDP, or the contribution to GDP growth attributable to the northern region of the country, will continue at the recent pace or at all.

A reduction in private or public construction projects in the northern region of Peru will have a material adverse effect on our business, financial condition and results of operations.

We estimate that in 2010 approximately 25% of our cement sales were derived from private construction (other than auto-construcción ) and 16% from public construction in the north of Peru. Significant interruptions or delays in, or the termination of, private or public construction projects may adversely affect our business, financial condition and results of operations. Private and public construction levels in our market depend on investments in the region which, in turn, are affected by economic conditions.

The level of public infrastructure construction also depends, to a great extent, on the priorities and financial resources of the national, regional and local governmental authorities. The Peruvian government has recently promoted significant public spending in infrastructure projects in the north in response to an infrastructure shortage and to stimulate the economy in response to the negative effects of recent global economic and financial crisis. We cannot assure you that the Peruvian government will continue promoting recent levels of public infrastructure spending in our market. A reduction in public infrastructure spending in our market would adversely affect our business, financial condition and results of operations.

Our business, financial condition and results of operations may be adversely affected by increases in energy prices or shortages in the supply of energy.

Energy represents a significant percentage of our production costs. Our principal energy sources are coal and electricity. In 2010, the cost of energy represented approximately 36.5% of our cement production costs. We use a substantial amount of coal as a source of fuel in our production process. We purchase anthracite coal from domestic suppliers and import bituminous coal from suppliers primarily in Colombia, in each case at market prices. We do not have long-term coal supply agreements, and we do not engage in hedging transactions in

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connection with the price of coal. Any shortage or interruption in the supply of coal could also disrupt our operations. In addition, the price of coal is largely driven by the price of oil, and, as a result, increases in international oil prices are likely to affect the price of coal and adversely affect our results of operations.

We have a long-term electricity supply agreement with Electroperú S.A. ("Electroperú"), a government-owned company, and a separate electricity supply agreement with Kallpa Generación S.A. ("Kallpa"), which expires in July 2012, to serve the electricity requirements of our Pacasmayo facility. We have also entered into a supply agreement with Electro Oriente S.A. ("ELOR") to supply the Rioja facility. Our business, financial condition and results of operations could be materially and adversely affected by higher costs, interruptions, and unavailability or shortage of electricity. We have no back-up power system at our plants and cannot assure you that, in case of interruption or failure in Electroperú's, Kallpa's or ELOR's operations, we will have access to other energy sources at the same prices and conditions, which could adversely affect our business, financial condition and results of operations. Moreover, electricity to our plants is transmitted through the Peruvian Electricity Interconnection System ( Sistema Eléctrico Interconectado Nacional del Perú , or "SEIN"). Any interruptions or failures in SEIN's system would also have a material adverse effect on our business, financial condition and results of operations.

In the recent past, we have experienced electricity rationing, limiting our use of electricity to certain times of the day. In such cases, we were forced to readjust our production schedules in order to ensure that our production process was not interrupted. In the event of any future rationing of electricity, we may not be able to readjust quickly enough and our production process may be interrupted. Future shortages or efforts to respond to or prevent shortages, such as rationing, may adversely impact the cost or supply of electricity for our operations.

A significant increase in the prices of coal or electricity would increase our costs of production. We may not be able to increase the prices of our cement products in the future if the prices of coal or electricity rises, which would adversely affect our business, financial condition and results of operations.

Changes in the cost or availability of admixtures and raw materials supplied by third parties may adversely affect our business, financial condition and results of operations.

We use certain admixtures and raw materials in the production of cement, such as gypsum, burn furnace slag and iron that we obtain from third parties. In 2010, our cost of admixtures and raw materials supplied by third parties as a percentage of our cement production costs was approximately 6.3%. We do not have long-term contracts for the supply of admixtures and raw materials that we use and if existing suppliers cease operations or reduce or eliminate production of these products, our costs to procure these materials may increase significantly or we may be obligated to procure alternatives to replace these products.

We may make future acquisitions that may not achieve expected benefits.

Our strategic initiatives include pursuing acquisitions that tend to diversify our existing portfolio of products and services and expand our geographic footprint. In the future, we may decide to expand by acquiring other companies in Peru or abroad. Any future acquisitions will depend on our ability to identify suitable candidates, negotiate acceptable terms, and obtain financing for the acquisitions. If future acquisitions are significant, they could change the scale

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of our business and expose us to new geographic, political, operating and financial risks. In addition, each acquisition involves a number of risks, such as the diversion of our management's attention from our existing business to integrating the operations and personnel of the acquired business, possible adverse effects on our results of operations during the integration process, our inability to achieve the intended objectives of the combination and potential unknown liabilities associated with the acquired assets.

We may not be able to obtain the funding required to implement future strategies.

Our strategies to continue to expand our cement production capacity and distribution network and to develop our brine and phosphate projects require significant capital expenditures. We cannot assure you that we will generate sufficient cash flow from operations, or that we will have access to external financing sources, to adequately fund such capital expenditures. Our access to external sources of financing will depend on many factors, including factors beyond our control, such as conditions in the global capital markets and investors' risk perception of investing in Peru and in emerging markets generally. Any equity or debt financing, if available, may not be on terms that are favorable to us. If our access to external financing is limited, we may not be able to execute our strategy, which could adversely affect our business, financial condition and results of operations.

We are subject to risks related to litigation and administrative proceedings that could adversely affect our business and financial performance in the event of an unfavorable ruling.

The nature of our business exposes us to litigation relating to product liability claims, labor, health and safety matters, environmental matters, regulatory, tax and administrative proceedings, governmental investigations, tort claims and contract disputes, among other matters. In the past, we have been subject to antitrust and tax proceedings or investigations. While we contest these matters vigorously and make insurance claims when appropriate, litigation is inherently costly and unpredictable, making it difficult to accurately estimate the outcome of actual or potential litigation. Although we establish provisions as we deem necessary, the amounts that we reserve could vary significantly from any amounts we actually pay due to the inherent uncertainties in the estimation process. We cannot assure you that these or other legal proceedings will not materially affect our ability to conduct our business, financial condition and results of operations in the event of an unfavorable ruling.

Our business is subject to a number of operational risks, which may adversely affect our business, financial condition and results of operations.

Our business is subject to several industry-specific operational risks, including accidents, natural disasters, labor disputes and equipment failures. Such occurrences could result in damage to our production facilities, and equipment and/or the injury or death of our employees and others involved in our production process. Moreover, such accidents or failures could lead to environmental damage, loss of resources or intermediate goods, delays or the interruption of production activities and monetary losses, as well as damage to our reputation. Our insurance may not be sufficient to cover losses from these events, which could adversely affect our business, financial condition and results of operations.

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In addition, key equipment at our facilities, such as our mills and kilns, may deteriorate sooner than we currently estimate. Such deterioration of our assets may result in additional maintenance or capital expenditures, and could cause delays or the interruption of our production activities. If these assets do not generate the cash flows we expect, and we are not able to procure replacement assets in an economically feasible manner, our business, financial condition and results of operations may be materially and adversely affected.

Our business depends on the continued operation of our flagship Pacasmayo plant.

Our flagship production facility in Pacasmayo is essential to our business. In 2010, approximately 89.2% of our total cement and all of our quicklime was produced at this facility. The Pacasmayo plant is subject to normal hazards of operating any cement production facility, including accidents and natural disasters. Any interruption in our operation of the Pacasmayo facility or a decrease in the effective capacity of this facility would adversely affect our results of operations, and any prolonged disruption in the operation of this facility would have a material adverse effect on our business, financial condition and results of operations.

The introduction of cement substitutes into the market and the development of new construction techniques could have a material adverse effect on our business, financial condition and results of operations.

Materials such as plastic, aluminum, ceramics, glass, wood and steel can be used in construction as a substitute for cement. In addition, other construction techniques, such as the use of dry wall, could decrease the demand for cement and concrete. In Peru, dry wall has only been introduced into the housing construction market in recent years and it is not widely used. However, the use of dry walls for housing construction could increase significantly in the future as it becomes more popular. In addition, research aimed at developing new construction techniques and modern materials may introduce new products in the future. The use of substitutes for cement could cause a significant reduction in the demand and prices for our cement products.

Our success depends on key members of our management.

Our success depends largely on the efforts and strategic vision of our executive management team and board of directors. The loss of the services of some or all of our executive management and members of our board of directors could have a material adverse effect on our business, financial condition and results of operations.

The execution of our business plan also depends on our ongoing ability to attract and retain additional other qualified employees capable of operating our plants. Due to the limited pool of skilled workers in the north of Peru or workers from other regions willing to relocate to the north of Peru, we may not be successful in attracting and retaining the personnel we require. If we are unable to hire, train and retain qualified employees at a reasonable cost, we may be unable to successfully operate our business or reach full planned production levels in a timely manner and, as a result, our business, financial condition and results of operations could be adversely affected.

Our operations and sales are highly concentrated in the northern region of Peru.

All of our operations are located in the northern region of Peru, including our production facilities and the quarries from where we obtain limestone to produce cement. In addition,

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substantially all of our cement products are sold to consumers in this market. As a result, any adverse economic, political or social conditions affecting the northern region of Peru, as well as natural disasters and weather conditions, such as the El Niño climate pattern, among other factors that may affect this region, could have a material adverse affect on our business, financial condition and results of operations.

We are subject to environmental regulations and may be exposed to liability and political cost as a result of our handling of hazardous materials and potential costs for environmental compliance.

We are subject to various environmental protection and health and safety laws and regulations that regulate, among other things, the generation, storage, handling, use and transportation of hazardous materials; emissions and discharge of hazardous materials; and the health and safety of our employees. Pursuant to Peruvian law, in order to conduct mining and industrial activities, we are required, among other things, to (i) submit an environmental study and a mining closure plan to the Ministry of Production ( Ministerio de la Producción ) prior to initiating mining activities, (ii) comply with certain air emission and wastewater discharge standards, (iii) obtain approval from the water management authority to discharge wastewater into natural water sources or soil, and (iv) dispose solid waste generated by us in special landfills exclusively through companies registered with the environmental agency. In addition, we are required to have a health and safety committee and develop an internal health and safety code. Although we believe we are in compliance with all these regulations in all material respects, we cannot assure you that we have been or will be at all times in full compliance with these laws and regulations. Any violation of such laws or regulations could result in substantial fines, criminal sanctions, revocations of operating permits and shutdowns of our facilities. In addition, current or future governments may also impose stricter regulations which may require us to incur higher compliance costs.

Pursuant to certain applicable environmental laws, we could be found liable for all or substantially all of the damages caused by pollution at our current or former facilities or those of our predecessors or at disposal sites. We could also be found liable for all incidental damages due to the exposure of individuals to hazardous substances or other environmental damage.

We cannot assure you that our costs of complying with current and future environmental and health and safety laws and regulations, and any liabilities arising from past or future releases of, or exposure to, hazardous substances will not adversely affect our business, financial condition and results of operations.

International agreements related to climate change may result in an increase in our costs.

There are ongoing international efforts to address greenhouse emissions. The United Nations and certain international organizations have taken action against activities that may increase the atmospheric concentration of greenhouse gases. Regulatory measures, such as the Kyoto Protocol, aimed at addressing greenhouse gas emissions and climate changes, are in various stages of negotiation and implementation. Such measures may result in an increase in costs to us for installation of new controls aimed at reducing greenhouse gas emissions, purchase of credits or licenses for atmospheric emissions, and monitoring and registration of greenhouse

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gas emissions from our operations. These measures, if adopted in Peru, could adversely affect our business, financial condition and results of operations.

Changes in regulations or in the interpretation of regulations may adversely affect our business, financial condition and results of operations.

Our business is subject to extensive regulation in Peru, including, among others, relating to tax, environmental, labor, health and safety, and mining matters. We believe that our facilities are currently operating in all material respects in accordance with all applicable concessions, laws and regulations. Future regulatory changes, changes in the interpretation of such regulations or stricter enforcement of such regulations, including changes to our concession agreements, may increase our compliance costs and could potentially require us to alter our operations. We cannot assure you that regulatory changes in the future will not adversely affect our business, financial condition and results of operations.

A dispute with the labor unions that represent our employees could have an adverse effect on our business, financial condition and results of operations.

As of September 30, 2011, approximately 16% of our employees were members of employee unions. Our practice is to extend some of the benefits we offer our unionized employees to other employees. Although we consider our relations with our employees are currently positive, we cannot assure you that we will not experience work slowdowns, work stoppages, strikes or other labor disputes in the future, which could adversely affect our business, financial condition and results of operations.

New projects may require the prior approval of local indigenous communities.

On September 7, 2011, Peru enacted Law No. 29,785, regarding the Prior Consultation Right of Local Indigenous Communities, in accordance with the International Labor Organization Convention No. 169 ( Ley del Derecho a la Consulta Previa a los Pueblos Indígenas y Originarios, Reconocido en el Convenio 169 de la Organización Internacional del Trabajo ). This law, which became effective on December 6, 2011, establishes a prior consultation procedure ( procedimiento de consulta previa ) that the Peruvian government must carry out with local indigenous communities whose rights may be directly affected by new legislative or administrative measures, including the granting of new mining concessions. Local indigenous communities do not have a veto right; upon completion of this prior consultation procedure, the Peruvian government retains the discretion to approve or reject the applicable legislative or administrative measure. However, to the extent that in the future our new projects require legislative or administrative measures that impact local indigenous communities, we may not be able to undertake such projects, unless the Peruvian government first conducts the foregoing consultation procedure. In addition, regulation implementing this law is still pending. We cannot assure you that this law will not adversely affect our new projects and have an adverse effect on our business, financial condition and results of operations.

Additional risks relating to our phosphate and brine projects

We have not established reserves with respect to our phosphate or brine projects.

We have not established reserves with respect to our phosphate or brine projects. We have only verified mineralized material in our phosphate deposits, and both projects are undergoing

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pre-feasibility studies. Such mineralized material will not qualify as reserves until a comprehensive evaluation, based upon unit costs, grades, recoveries and other factors, concludes economic and legal feasibility. The cost, timing and complexities of upgrading mineralized material to reserves may be greater than we anticipate. Mineral exploration and development involves a high degree of risk that even a combination of careful evaluation, experience and knowledge cannot eliminate, and few properties that are explored are ultimately developed into producing mines. Once mineralization is discovered, it may take a number of years from the initial phases of drilling before production is possible, during which time the economic feasibility of production may change. Substantial expenditures typically are required to establish reserves through drilling, to determine metallurgical processes to extract the minerals from the ore and to construct mining and processing facilities.

We cannot assure you that we will be able to establish the presence of any reserves for phosphate or brine. The failure to establish reserves would materially affect our ability to develop our phosphate and brine projects and could significantly reduce their estimated value.

Mineralized material calculations are only estimates.

Our calculation of the mineralized material at our Bayóvar field is only an estimate and depends on geological interpretation and statistical inferences or assumptions drawn from drilling and sampling analysis, which may prove to be materially inaccurate. There is a significant degree of uncertainty attributable to the calculation of mineralized material. Until mineralized material is actually mined and processed, the quantity of mineralized material and grades must be considered as estimates only and we cannot assure you that indicated levels will actually be produced.

The estimate of mineralized material is partially dependent upon the judgment of the person preparing the estimates. The process relies on the quantity and quality of available data and is based on knowledge, mining experience, statistical analysis of drilling results and industry practices. Valid estimates at a given time may significantly change when new information becomes available.

Estimating mineralized material may have to be recalculated based on further exploration or development activity or actual production experience, which could materially and adversely affect estimates of the quantity or grade of mineralized material. Any material changes in quantity and grades of mineralized material will affect the economic viability of placing a property into production and a property's return on capital. We cannot assure you that mineralized material can be mined or processed profitably.

Our phosphate and brine projects are not part of our core cement business and we cannot assure you that we will be able to profitably extract and sell these products.

We are undertaking two non-metallic mining projects to develop phosphate and brine deposits. However, we have only initiated pre-feasibility studies and we cannot assure you that these projects will be successful or profitable. Mining is highly speculative in nature, involves many risks and can be unsuccessful. In addition, our core competency is the production and distribution of cement products. We have no prior experience in planning, developing and managing large-scale mining projects, and we have no operating experience or track record in extracting, processing or commercializing phosphate or brine minerals to assess our potential performance. The development of these two projects may result in unforeseen operating

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difficulties and may require significant financial and managerial resources that would otherwise be available for the ongoing development of our existing cement operations.

We may face several factors that may impair our ability to execute these projects successfully including, among others, the following:

•

delays in obtaining regulatory approvals, licenses or permits from different governmental or regulatory authorities, including environmental permits;

•

increases in the cost of energy, equipment, materials or labor, making the project economically unfeasible;

•

adverse weather conditions, natural disasters, accidents or other unforeseen events;

•

unforeseen engineering, design, environmental or geological problems;

•

insufficient access to adequate means of transportation for our minerals, including delays in the construction of a port nearby;

•

opposition from local communities;

•

strikes or labor disputes;

•

changes in the level of demand and prices for products derived from these materials; and

•

adverse changes in Peru's regulatory framework.

Any of these factors may delay our projects and may increase our projected capital costs. If we are unable to complete these projects, any costs incurred in connection with these projects may not be recoverable. If we experience delays, cost overruns, or changes in market circumstances, we may not be able to demonstrate the commercial viability of these projects or achieve the intended economic benefits, which would materially and adversely affect our business, financial condition and results of operations.

In addition, we may face difficulties in marketing and distributing the products derived from these fields. Even if we successfully extract these minerals, we may not be able to market them successfully or find suitable buyers, which may have an adverse effect on our business, financial condition and results of operations.

The actual amount of capital required for our phosphate and brine projects may vary significantly from our current estimates.

Our phosphate and brine initiatives are complex projects that require significant capital investment. Our estimated capital amounts for these projects are based on preliminary estimates and assumptions we have made about the mineral deposits, equipment, labor, permits and other factors required to complete the projects. If any of these estimates or assumptions change, the actual timing and amount of capital required may vary significantly from what we anticipate. Additional funds may be required in the event of departures from current estimates, unforeseen delays, cost overruns, engineering design changes or other unanticipated expenses, or if we are unable to find a suitable strategic partner to assist in financing our phosphate project. We cannot assure you that additional financing will be

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available to us, or, if available, that it can be obtained on a timely basis and on commercially acceptable terms.

If we have difficulties working with Mitsubishi to develop our phosphate project or with Quimpac to develop our brine project, we may face difficulties in carrying out these projects.

We are unfamiliar with the commercial market for phosphate and brine products and are seeking to develop these projects with partners that have expertise in commercializing these products. We sold a minority equity interest in our subsidiary Fosfatos to an affiliate of Mitsubishi, which will assist us to develop our phosphate deposits. In addition, Mitsubishi entered into a 20-year off-take agreement with Fosfatos. We have formed Salmueras with Quimpac as a minority partner to assist in financing our brine project and provide its expertise in the commercialization of dicalcium phosphate and salt. If we encounter difficulties working with Mitsubishi or Quimpac, we may not be able to execute these projects as currently contemplated.

Risks relating to the offering

The market price of our ADSs may fluctuate significantly, and you could lose all or part of your investment.

Volatility in the market price of our ADSs may prevent you from being able to sell your ADSs at or above the price you paid for them. The market price and liquidity of the market for our ADSs may be significantly affected by numerous factors, some of which are beyond our control and may not be directly related to our operating performance. These factors include, among others:

•

actual or anticipated changes in our results of operations, or failure to meet expectations of financial market analysts and investors;

•

investor perceptions of our prospects or our industry;

•

operating performance of companies comparable to us and increased competition in our industry;

•

new laws or regulations or new interpretations of laws and regulations applicable to our business;

•

general economic trends in Peru;

•

catastrophic events, such as earthquakes and other natural disasters; and

•

developments and perceptions of risks in Peru and in other countries.

You may not be able to sell ADSs you own or the common shares underlying the ADSs at the time or the price you desire because an active or liquid market for these securities may not develop.

Prior to this offering, there has not been a public market for our ADSs. We have applied to list our ADSs on the New York Stock Exchange. We cannot predict whether an active liquid public trading market for our ADSs will develop or be sustained. Active, liquid trading markets generally result in lower price volatility and respond more efficiently to orders from investors

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to purchase or sell securities. Liquidity of a securities' market is often a function of the volume of the underlying shares that are publicly-held by unrelated parties. Our common shares are listed on the Lima Stock Exchange. Although ADS holders are entitled to withdraw common shares underlying our ADSs from the depositary at any time, the Lima Stock Exchange in Peru is generally a less liquid trading market than the New York Stock Exchange.

Substantial sales of ADSs or common shares after this offering could cause the price of our ADSs or common shares to decrease.

Our controlling shareholder will continue to hold a large number of our common shares after this offering. We and our controlling shareholder, among others, will agree with J.P. Morgan Securities LLC not to offer, sell, contract to sell or otherwise dispose of or hedge any common shares, investment shares, or ADSs, without the prior written consent of J.P. Morgan Securities LLC, during the 180 calendar day period following the date of the prospectus, subject to certain exceptions. After this 180 day period expires, these securities will be eligible for sale. The market price of our ADSs could decline significantly if we or our controlling shareholder sell securities in our company or the market perceives that we or our controlling shareholder intend to do so.

In connection with this offering, under Peruvian law we are required to launch a preemptive rights offer of [    •    ] non-voting investment shares to existing holders of our investment shares at the nuevo sol equivalent of the price per ADS offered hereby, which could affect the trading price of our ADSs. The preemptive rights offer will be launched one business day after the date of this prospectus and will remain open for 18 business days thereafter.

Our controlling shareholder will continue to have significant influence over us after this offering, and his interests could conflict with yours.

Upon the consummation of the global offering, our controlling shareholder will beneficially own approximately [    •    ]% of our outstanding common shares (assuming no exercise of the over-allotment option). As such, our controlling shareholder has the ability to determine the outcome of substantially all matters submitted for a vote to our shareholders and thus exercise control over our business policies and affairs, including, among others, the following:

•

the composition of our board of directors and, consequently, any determinations of our board with respect to our business direction and policy, including the appointment and removal of our executive officers;

•

determinations with respect to mergers, other business combinations and other transactions, including those that may result in a change of control;

•

whether dividends are paid or other distributions are made and the amount of any such dividends or distributions;

•

whether we offer preemptive and accretion rights to holders of our common shares in the event of a capital increase;

•

sales and dispositions of our assets; and

•

the amount of debt financing that we incur.

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Our controlling shareholder may direct us to take actions that could be contrary to your interests and may be able to prevent other shareholders, including you, from blocking these actions or from causing different actions to be taken. Also, our controlling shareholder may prevent change of control transactions that might otherwise provide you with an opportunity to dispose of or realize a premium on your investment in our ADSs. We cannot assure you that our controlling shareholder will act in a manner consistent with your best interests.

Holders of ADSs may be unable to exercise voting rights with respect to our common shares underlying the ADSs at our shareholders' meetings.

As a holder of ADSs representing common shares being held by the depositary in your name, you may exercise voting rights with respect to the common shares represented by the ADSs only in accordance with the deposit agreement relating to the ADSs. Holders of our common shares will receive notice of shareholders' meetings through publication of a notice in an official gazette in Peru, a Peruvian newspaper of general circulation and the bulletin of the Lima Stock Exchange, and will be able to exercise their voting rights by either attending the meeting in person or voting by proxy. ADS holders will not receive notice directly from us. Instead, pursuant to the deposit agreement, we will notify the depositary, who will mail to holders of ADSs the notice of the meeting and a statement as to the manner in which voting instructions may be given. To exercise their voting rights, ADS holders must instruct the depositary how to exercise the voting rights for the common shares which underlie their ADSs. Due to these additional procedural steps involving the depositary, the process for exercising voting rights may take longer for ADS holders than for holders of our common shares.

Holders of ADSs also may not receive voting materials in time to instruct the depositary to vote the common shares underlying their ADSs. In addition, the depositary and its agents are not responsible for failing to carry out voting instructions of the holders of ADS or for the manner of carrying out such instructions, unless such failure can be attribute to gross negligence, bad faith or willful misconduct on the part of the depositary or its agents. Accordingly, holders of ADSs may not be able to exercise voting rights, and they will have little, if any, recourse if the underlying common shares are not voted as requested.

Our shareholders' ability to receive cash dividends may be limited.

Our shareholders' ability to receive cash dividends may be limited by the ability of the depositary to convert cash dividends paid in nuevos soles into U.S. dollars. Under the terms of our deposit agreement with the depositary for the ADSs, the depositary will convert any cash dividend or other cash distribution we pay on the common shares underlying the ADSs into U.S. dollars, if it can do so on a reasonable basis and can transfer the U.S. dollars to the United States. If this conversion is not possible or if any government approval is needed and cannot be obtained, the deposit agreement allows the depositary to distribute the foreign currency only to those ADR holders to whom it is possible to do so. If the exchange rate fluctuates significantly during a time when the depositary cannot convert the foreign currency, you may lose some or all of the value of the dividend distribution.

Holders of ADSs may be unable to exercise preemptive or accretion rights with respect to the common shares underlying their ADSs.

Under Peruvian corporate law, if we issue new common shares as part of a capital increase, unless otherwise agreed to by holders of 40% of our outstanding common shares, our

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shareholders will generally have the right to subscribe to a proportional number of common shares of the class held by them to maintain their existing ownership percentage, which is known as preemptive rights. In addition, shareholders are entitled to the right to subscribe for the unsubscribed common shares of either the class held by them or other classes which remain unsubscribed at the end of a preemptive rights offering, on a pro rata basis, which is known as accretion rights. You may not be able to exercise the preemptive or accretion rights relating to common shares underlying your ADSs unless a registration statement under the Securities Act is effective with respect to those rights or an exemption from the registration requirements of the Securities Act is available. We are not obligated to file a registration statement with respect to the common shares relating to these preemptive and accretion rights, and we cannot assure you that we will file any such registration statement. Unless we file a registration statement or an exemption from registration is available, you may receive only the net proceeds from the sale of your preemptive and accretion rights by the depositary or, if the preemptive and accretion rights cannot be sold, they will be allowed to lapse. As a result, U.S. holders of our ADSs may suffer dilution of their interest in our company upon future capital increases.

We are entitled to amend the deposit agreement and to change the rights of ADS holders under the terms of such agreement, without the prior consent of the ADS holders.

We are entitled to amend the deposit agreement and to change the rights of the ADS holders under the terms of such agreement, without the prior consent of the ADS holders. Any change related to an increase in deposits or charges for book-entry securities services or any modification that might hinder the rights of the ADS holders will be effective within 30 days after the ADS holders have received notice of such change or modification and such holders will have no right to any compensation whatsoever.

Our status as a foreign private issuer allows us to follow alternate standards to the corporate governance standards of the New York Stock Exchange, which may limit the protections afforded to investors.

We are a "foreign private issuer" within the meaning of the New York Stock Exchange corporate governance standards. Under New York Stock Exchange rules, a foreign private issuer may elect to comply with the practices of its home country and not to comply with certain corporate governance requirements applicable to U.S. companies with securities listed on the exchange. We currently follow certain Peruvian practices concerning corporate governance and intend to continue to do so. Accordingly, holders of our ADSs will not have the same protections afforded to shareholders of companies that are subject to all New York Stock Exchange corporate governance requirements.

For example, the New York Stock Exchange listing standards provide that the board of directors of a U.S. listed company must have a majority of independent directors at the time the company ceases to be a "controlled company". Under Peruvian corporate governance practices, a Peruvian company is not required to have a majority of independent members on its board of directors.

The listing standards for the New York Stock Exchange also require that U.S. listed companies, at the time they cease to be "controlled companies", have a nominating/corporate governance committee and a compensation committee (in addition to an audit committee). Each of these

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committees must consist solely of independent directors and must have a written charter that addresses certain matters specified in the listing standards. Under Peruvian law, a Peruvian company may, but is not required to, form special governance committees, which may be composed partially or entirely of non-independent directors.

In addition, New York Stock Exchange rules require the independent non-executive directors of U.S. listed companies to meet on a regular basis without management being present. There is no similar requirement under Peruvian law.

The New York Stock Exchange's listing standards also require U.S. listed companies to adopt and disclose corporate governance guidelines. In July 2002, the Peruvian Securities Commission and a committee comprised of regulatory agencies and associations prepared and published a list of suggested non-mandatory corporate governance guidelines called the "Principles of Good Governance for Peruvian Companies." Although we have implemented a number of these measures, we are not required to comply with the corporate governance guidelines by law or regulation.

Minority shareholders in Peru are not afforded equivalent protections as minority shareholders in other jurisdictions and investors may face difficulties in commencing judicial and arbitration proceedings against our company or the controlling shareholder.

Our company is organized and existing under the laws of Peru, and our controlling shareholder is resident in Peru. Accordingly, investors may face difficulties in serving process on our company, our officers and directors or the controlling shareholder in other jurisdictions, and in enforcing decisions granted by courts located in other jurisdictions against our company, our officers and directors or the controlling shareholder that are based on securities laws of jurisdictions other than Peru.

In Peru, there are no proceedings to file class action suits or shareholder derivative actions with respect to issues arising between minority shareholders and an issuer, its controlling shareholders or directors and officers. Furthermore, the procedural requirements to file actions by shareholders differ from those of other jurisdictions, such as in the United States. As a result, it may be more difficult for our minority shareholders to enforce their rights against us, our directors, officers or controlling shareholder as compared to the shareholders of a U.S. company. The deposit agreement provides that the depositary has no obligation to commence or become involved in any judicial proceedings and any other legal actions relating to the ADSs or the deposit agreement, either on behalf of the ADS holders or on behalf of any other person.

You will experience immediate and substantial dilution in the book value of the common shares and ADSs you purchase in this offering.

Because the initial offering price of the ADSs being sold in this offering will be substantially higher than our net tangible book value per common share, you will experience immediate and substantial dilution in the book value of the common shares underlying your ADSs. Net tangible book value represents the amount of our tangible assets on an adjusted basis, minus our total liabilities on an adjusted basis. As a result, at the assumed initial public offering price of US$[    •    ] per ADS, or US$[    •    ] per common share (based on the mid-point of the price range set forth on the cover page of this prospectus), we currently expect that you will incur immediate dilution of US$[    •    ] per ADS, or US$[    •    ] per common share, you purchase in

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this offering (assuming no exercise of the underwriters' over-allotment option and no purchase under the preemptive rights offer).

Our newly issued common shares from this offering will initially be represented by " certificados provisionales " and you will not be able to cancel your ADSs and withdraw the deposited common shares until the definitive common shares are issued.

In accordance with Peruvian law, our common shares will be represented by preliminary stock certificates (certificados provisionales) until the capital increase is recorded with the Peruvian public registry and new common shares are listed on the Lima Stock Exchange and registered in the CAVALI S.A. ICLV book-entry settlement system. We cannot assure you that the Peruvian public registry will not delay the recording of our capital increase. In addition, the corporate resolution authorizing the capital increase may be subject to judicial challenges or other factors that prevent or delay the recording of the capital increase with the Peruvian public registry. Once the capital increase has been recorded, we will issue common shares in exchange for the preliminary stock certificates. Only after the capital increase has been recorded with the Peruvian public registry and we have issued common shares in exchange for the preliminary stock certificates, will you be able to cancel your ADSs and withdraw the deposited common shares.

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Exchange rates

The Peruvian nuevo sol is freely traded in the exchange market. Current Peruvian regulations on foreign investment allow foreign equity holders of Peruvian companies to receive and repatriate 100% of the cash dividends distributed by these companies. Non-Peruvian equity holders are allowed to purchase foreign currency at free market currency rates through any member of the Peruvian banking system and transfer such foreign currency outside Peru without restriction. Peruvian law in the past, however, has imposed restrictions on the conversion of Peruvian currency and the transfer of funds abroad, and we cannot assure you that Peruvian law will continue to permit such payments, transfers, conversions or remittances without restrictions.

The following table sets forth, for the periods indicated, certain information regarding the exchange rates for nuevos soles per U.S. dollar, as published by the SBS. The Federal Reserve Bank of New York does not report a noon buying rate for nuevos soles.

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Use of proceeds

We estimate that the net proceeds to us from this offering will be approximately US$[    •    ] million, or US$[    •    ] million if the underwriters exercise the over-allotment option in full. These amounts assume an initial public offering price of US$[    •    ] per ADS (the mid-point of the price range set forth on the cover page of this prospectus), after deducting the estimated underwriting discounts and commissions and offering expenses payable by us. The following estimates assume the underwriters do not exercise the over-allotment option and holders of investment shares do not exercise the right to subscribe additional investment shares in the preemptive rights offer.

We intend to use approximately [    •    ]% of the net proceeds from this offering for capital expenditures and other general corporate purposes to grow our core cement business. The capital expenditures will include the increase of cement production capacity of our Rioja facility, which is currently operating at near full capacity, and part of the construction of a cement plant in Piura based on the results of our pre-feasibility and engineering studies. We believe that our expansion plans will allow us to meet projected increases in demand for cement in coming years, help us deepen our commercial relationships in regional areas in our market, reduce transportation costs, and secure our leadership position in the northern region of Peru. We routinely evaluate acquisition and investment opportunities that are aligned with our strategic goals, so we may also acquire, or invest in, businesses, technologies or products that are complementary to our core business. We will have broad discretion over the uses of the net proceeds from this offering.

We currently also expect to use approximately [    •    ]% of the net proceeds from this offering toward capital expenditures required to develop our phosphate and brine projects. Our preliminary estimates of the investments required to develop these projects are in the range of US$350 to US$400 million for phosphate and in the range of US$250 to US$300 million for brine. These estimates, however, are based on limited preliminary work and are subject to change. We have not developed a specific timetable for the development of these projects and our use of proceeds may vary depending on the progress and ongoing evaluation of these projects. We expect to finance these projects with a combination of the net proceeds from this offering, new borrowings and financial contributions from current or future minority partners. We will have significant flexibility in applying the net proceeds of this offering to these projects.

Pending application of the net proceeds, we expect to invest the proceeds in low-risk marketable securities, bank deposits and money market funds.

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